试题与答案

设{an}是公差d不为零的正项等差数列,Sn为其前n项的和,满足5S3-6S5=

题型:解答题

题目:

设{an}是公差d不为零的正项等差数列,Sn为其前n项的和,满足5S3-6S5=-105,a2,a5,a14成等比数列.
(1)求数列{an}的通项公式;
(2)设c∈N,c≥2,令bn=|
an
2c-1
-1|
,Tn为数列{bn}的前n项的和,若T2c≤6,求c的值.

答案:

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参考答案:B

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